Fuck this society and its capitalism, there's the root of the problem of fast food.
Fast food is a drug, no doubt about that. It lures you in young with advertisements making it look "cool" and the bribe that is the happy meal toy. Then you are hooked for life. Not to mention it is CHEAP and available 24/7.
With that said I eat fast food several times a week, though not every day and certainly never 2 times a day unless I am on a roadtrip that lasts more than 8 hours. Also, I eat at places like Subway which aren't as bad as the fried food establishments.
Moreso than the food and its content, fast food is bad because it creates waste, waste, and more WASTE. You need a wrapper for the burger, a container for the fries, a cup for the drink and even though you aren't in the car you need to put a lid and use a straw for that drink. Just another American addiction, that of unnecessary packaging.